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OPEN
Stygofauna enhance prokaryotic transport in groundwater ecosystems
received: 25 May 2016
Renee J. Smith1, James S. Paterson1, Elise Launer1, Shanan S. Tobe1,2, Eliesa Morello1, Remko Leijs1,3, Shashikanth Marri4 & James G. Mitchell1
accepted: 15 August 2016 Published: 06 September 2016
More than 97% of the world’s freshwater reserves are found in aquifers, making groundwater one of the most important resources on the planet. Prokaryotic communities in groundwater underpin the turnover of energy and matter while also maintaining groundwater purity. Thus, knowledge of microbial transport in the subsurface is crucial for maintaining groundwater health. Here, we describe for the first time the importance of stygofauna as vectors for prokaryotes. The “hitch-hiking” prokaryotes associated with stygofauna may be up to 5 orders of magnitude higher in abundance and transported up to 34× faster than bulk groundwater flow. We also demonstrate that prokaryotic diversity associated with stygofauna may be higher than that of the surrounding groundwater. Stygofauna are a newly recognized prokaryotic niche in groundwater ecosystems that have the potential to transport remediating, water purifying and pathogenic prokaryotes. Therefore, stygofauna may influence ecosystem dynamics and health at a microbial level, and at a larger scale could be a new source of prokaryotic diversity in groundwater ecosystems. Prokaryotes in terrestrial subsurface environments, which include groundwater, account for 40% of the global prokaryotic biomass, with overall abundance estimates of 4–6 × 1030 cells1. These prokaryotic communities play a fundamental role in the turnover of biosphere energy and matter2,3, while also purifying groundwater4. Prokaryotic communities typically consist of a mixed consortium, which allows for rapid responses to environmental perturbations5–7. This rapid response to change means that microbial communities are often tracked as biological indicators8,9. Thus, many studies have focused on the advection transport of prokaryotic communities in groundwater to determine ecosystem health9,10. The importance of prokaryotes in groundwater has highlighted the need for an improved understanding of the transport of microbial communities in subsurface environments11. Transport of microbes in the subsurface involves a host of complex physiochemical and biological parameters, including advection and prokaryotic motility11,12. Prokaryotes in groundwater can be motile13,14, however it has been observed that only a small fraction (
OPEN
Stygofauna enhance prokaryotic transport in groundwater ecosystems
received: 25 May 2016
Renee J. Smith1, James S. Paterson1, Elise Launer1, Shanan S. Tobe1,2, Eliesa Morello1, Remko Leijs1,3, Shashikanth Marri4 & James G. Mitchell1
accepted: 15 August 2016 Published: 06 September 2016
More than 97% of the world’s freshwater reserves are found in aquifers, making groundwater one of the most important resources on the planet. Prokaryotic communities in groundwater underpin the turnover of energy and matter while also maintaining groundwater purity. Thus, knowledge of microbial transport in the subsurface is crucial for maintaining groundwater health. Here, we describe for the first time the importance of stygofauna as vectors for prokaryotes. The “hitch-hiking” prokaryotes associated with stygofauna may be up to 5 orders of magnitude higher in abundance and transported up to 34× faster than bulk groundwater flow. We also demonstrate that prokaryotic diversity associated with stygofauna may be higher than that of the surrounding groundwater. Stygofauna are a newly recognized prokaryotic niche in groundwater ecosystems that have the potential to transport remediating, water purifying and pathogenic prokaryotes. Therefore, stygofauna may influence ecosystem dynamics and health at a microbial level, and at a larger scale could be a new source of prokaryotic diversity in groundwater ecosystems. Prokaryotes in terrestrial subsurface environments, which include groundwater, account for 40% of the global prokaryotic biomass, with overall abundance estimates of 4–6 × 1030 cells1. These prokaryotic communities play a fundamental role in the turnover of biosphere energy and matter2,3, while also purifying groundwater4. Prokaryotic communities typically consist of a mixed consortium, which allows for rapid responses to environmental perturbations5–7. This rapid response to change means that microbial communities are often tracked as biological indicators8,9. Thus, many studies have focused on the advection transport of prokaryotic communities in groundwater to determine ecosystem health9,10. The importance of prokaryotes in groundwater has highlighted the need for an improved understanding of the transport of microbial communities in subsurface environments11. Transport of microbes in the subsurface involves a host of complex physiochemical and biological parameters, including advection and prokaryotic motility11,12. Prokaryotes in groundwater can be motile13,14, however it has been observed that only a small fraction (
